r - 我不知道如何解决这个错误

Question

在此处上传 Divvy 数据集（csv 文件）

Oct_2020_tripdata <- read_csv("Oct 2020.csv")
Nov_2020_tripdata <- read_csv("Nov 2020.csv")
Dec_2020_tripdata <- read_csv("Dec 2020.csv")
Jan_2021_tripdata <- read_csv("Jan 2021.csv")
Feb_2021_tripdata <- read_csv("Feb 2021.csv")
Mar_2021_tripdata <- read_csv("Mar 2021.csv")

将相关列转换为字符，以便它们可以正确堆叠

Oct_2020_tripdata <-  mutate(Oct_2020_tripdata, start_station_id = as.character(start_station_id)
                             ,end_station_id = as.character(end_station_id))
Nov_2020_tripdata <-  mutate(Nov_2020_tripdata, start_station_id = as.character(start_station_id)
                             ,end_station_id = as.character(end_station_id))
Dec_2020_tripdata <-  mutate(Dec_2020_tripdata, start_station_id = as.character(start_station_id)
                             ,end_station_id = as.character(end_station_id))
Jan_2021_tripdata <-  mutate(Jan_2021_tripdata, start_station_id = as.character(start_station_id)
                             ,end_station_id = as.character(end_station_id))
Feb_2021_tripdata <-  mutate(Feb_2021_tripdata, start_station_id = as.character(start_station_id)
                             ,end_station_id = as.character(end_station_id))
Mar_2021_tripdata <-  mutate(Mar_2021_tripdata, start_station_id = as.character(start_station_id)
                             ,end_station_id = as.character(end_station_id))

绑定数据框

all_trips <- bind_rows(Oct_2020_tripdata, Nov_2020_tripdata, Dec_2020_tripdata, 
                       Jan_2021_tripdata, Feb_2021_tripdata, Mar_2021_tripdata)

删除缺少值的行

colSums(is.na(all_trips))
all_trips_cleaned <- all_trips[complete.cases(all_trips), ]

过滤大于ended_at 的started_at 数据

all_trips_cleaned <- all_trips_cleaned %>% 
  filter(all_trips_cleaned$started_at < all_trips_cleaned$ended_at)

创建新列以列出每次骑行的日期、月份、日期和年份

all_trips_cleaned$date <- as.Date(all_trips_cleaned$started_at, format= "%m/%d/%Y")
all_trips_cleaned$month <- format(as.Date(all_trips_cleaned$date), "%m")
all_trips_cleaned$day <- format(as.Date(all_trips_cleaned$date), "%d")
all_trips_cleaned$year <- format(as.Date(all_trips_cleaned$date), "%Y")
all_trips_cleaned$day_of_week <- format(as.Date(all_trips_cleaned$date), "%A")

尝试添加一个新列以使用 R 将每个骑行长度（以秒为单位）计算为数字

all_trips_cleaned$ride_length <- as.numeric(difftime(all_trips_cleaned$ended_at, all_trips_cleaned$started_at))

这是我收到的错误消息：

Error in as.POSIXlt.character(x, tz, ...) : 
  character string is not in a standard unambiguous format

标签： rdifftimeposixlt